1. Field of the Invention
This invention pertains to an improved divider block for use in displacement engines and pumps of the type disclosed in my U.S. Pat. No. 3,877,442, filed Oct. 5, 1973.
Such machines in principle employ a pair of parallel gear wheels having circularly disposed teeth on their faces which intermesh to define sealed working chambers within a generally annular cavity. These chambers each compress and expand twice per one revolution of the wheels, enabling adaptation as a 4-stroke combustion engine or for pump, compressor or fluid motor applications. While inherently providing a dual volumetric displacement, the principle may be modified, as originally disclosed, to provide only a single displacement, if desired.
2. Description of Prior Art
According to the cycle employed, the housing in these machines can be configured with either single or twin intake and exhaust ports, requiring respectively, either one or two divider blocks, each of which separates, as does a partition wall, the intake port of one displacement section from the exhaust port of the opposite displacement section. The divider blocks comprise a part of the housing entirety, although not contiguous thereto, but are dowelled to adjoining spacer plates which surround the gear wheels. The inner or interior surfaces of the blocks and housing are semi-cylindrical for sealing engagement by the curved surfaces of the teeth of the gear wheels. The lateral or face surfaces of the blocks and housing are sealingly contacted by the respective faces of the disc portions of the gear wheels to define sealed working chambers between the gear teeth.
In conjunction with a core member which is fixed or non-rotatively supported within the cage defined by the intermeshing teeth of the two gear wheels, each divider block defines a narrow pass through which the teeth of the gear wheels merge in single-file passage during rotation.
The divider blocks should be made as thin as possible, which is to say that the adjacent intake and exhaust ports should be closely spaced so as not to expend undue angular rotational movement of the gear wheels for porting. The minimum thickness a divider block may be reduced to, however, considering static rather than dynamic compression or expansion, is that point where no free communication or leakage occurs around the teeth and through the ported pass.
As will become hereinafter more lucid, there exists obscurely in the machines of the prior patent some slight free communication at the ported passes in certain rotative positions of the gear teeth. This can be disadvantageous or inconsequential, depending upon the intended type of service. The improvement as herein disclosed prevents or reduces leakage through the ported passes or between the two displacement sections in any rotative position of the gear teeth.